Dough-based baked food products having a high water content (e.g., tortillas, bread, bagels and other bakery goods) are particularly susceptible to food spoilage problems caused by the unwanted growth of bacteria, yeasts and molds. In order to prevent microbial spoilage, such products are often treated with preservatives to inhibit yeast, bacteria, and/or mold growth and thereby extend the shelf life of the product. Such preservatives may include calcium propionate, sorbic acid, and benzoic acid, and typically function by preventing microbes from producing the requisite energy needed to grow and reproduce.
An acidic environment in foodstuffs has been found to act synergistically with these preservatives, showing an increase in shelf-life over food products solely containing the preservatives at a neutral pH. In order to stabilize the antimicrobial preservatives that generally perform better in high acidity levels, it is known to add acidulates, such as fumaric acid, to the food product to reduce pH levels and provide an optimal acidic environment. Specifically, acidulates are added to foodstuffs to reduce the pH level of a dough to at or near the acid dissociation constant (“pKa”) of the particular preservative also contained therein. When the pH of the dough approaches the pKa of the added preservative, the conjugated acid form of the preservative is mostly available and therefore optimally effective at reducing microbial growth.
Adding an acidulate, such as fumaric acid, citric acid, malic acid, lactic acid, or ascorbic acid, to dry dough mixtures has proven to successfully increase the shelf life of food products in most cases. However, the addition of such acidulates to the dry mix presents problems for the resulting baked goods. For example, when such acidulates, or food acids, are added to dry bread mix, a negative effect is seen on the proteins (gluten) in the bread end product. This occurs because the elasticity of gluten is influenced by pH and a finished baked product resulting from an acidic dough tends to exhibit a denser size per mass, thereby resulting in a baked product having a decreased height and diameter.
Further, the addition of acidulates to dough can also have a negative effect on the chemical leavening system therein, resulting in low volume baked products. Typically, chemical leavening systems include a leavening acid and a leavening base (i.e. sodium bicarbonate). In most leavened products, the base is added to the dry dough mix and the acid portion is added just prior to baking. Accordingly, the leavening acid and base ideally do not react until the baking process (i.e. when the dough is heated), thereby preventing the formation of carbon dioxide until the dough cell walls are prepared to expand and trap the gas therein.
However, when an acidulate is added for preservation purposes, the acidulate dissolves at the initial stages of mixing and immediately begins to react with the dissolved leavening base. In this manner, the formation of carbon dioxide occurs prematurely and the leavening base is fully reacted prior to the baking stage. As a result, during the baking stage when the leavening gases should be produced, an insufficient amount of leavening base exists within the batter to react with the leavening acid and the rising capability of the dough is depleted. Accordingly, the addition of preservative acids to the dry dough mix can lead to many undesirable physical qualities in the finished product, some of which have been previously mentioned above.
In order to avoid some of the problems associated with prematurely acidifying dough, acidulates having low solubility have been commonly used. The advantage of using an acidulate having a low solubility is that the acidulate does not dissolve quickly into the dough mix during mixing and baking and, thus, decreases the pH of the mix more slowly than acidulates with higher solubilities. Fumaric acid is an example of such an acidulate and is commonly selected for its low solubility. If a low pH is delayed, a reduction in the deleterious effects to the gluten and the chemical leavening system will result. However, despite the low solubility of fumaric acid and other similar acidulates, even these acidulates tend to dissolve prematurely and sufficiently lower the pH of the dough mix such that some negative effects are produced in the finished product.
In an attempt to further delay the dissolution of acidulates into a dough mix, larger particle sizes of the acidulates have been employed, often ranging up to 300 microns. As is commonly known, the size of a particle is inversely proportional to the solubility of the particle (e.g., the larger the particle size, the slower the rate of dissolution). In addition, it is known to encapsulate the acidulate in a coating to further delay the dissolution of the fumaric acid into the dough mix.
Nevertheless, by increasing the resistance of the fumaric acid to dissolution through use of an increased particle size or using encapsulation techniques, the likelihood is greatly increased that the concentration of fumaric acid within the dough mix will be insufficient to adequately reduce the acidity of the dough mix to facilitate the activity of the preservative. In this manner, while the integrity of the gluten and chemical leavening system is left in tact, the product does not exhibit a satisfactory shelf-life due to its susceptibility to microbiological contamination. It has proven exceedingly difficult to achieve the desired time-dissolution profile for dough formation and baking with both of these methods. Accordingly, it is desirable to obtain a compound and/or a method that can be used to maintain or increase an extended “shelf-life” of the product in addition to increasing the volume of the end-product baked good.